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Upgrade protozero to version 1.5.2

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This commit is contained in:
Eric Fischer
2017-06-30 11:20:26 -07:00
parent bd845ac57d
commit 3ba45c7277
13 changed files with 1337 additions and 740 deletions
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protozero/byteswap.hpp
+47 -34
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@@ -16,56 +16,69 @@ documentation.
* @brief Contains functions to swap bytes in values (for different endianness).
*/
#include <cstdint>
#include <cassert>
#include <cstdint>
#include <protozero/config.hpp>
namespace protozero {
namespace detail {
/**
* Swap N byte value between endianness formats. This template function must
* be specialized to actually work.
*/
template <int N>
inline void byteswap(const char* /*data*/, char* /*result*/) {
static_assert(N == 1, "Can only swap 4 or 8 byte values");
}
/**
* Swap 4 byte value (int32_t, uint32_t, float) between endianness formats.
*/
template <>
inline void byteswap<4>(const char* data, char* result) {
inline uint32_t byteswap_impl(uint32_t value) noexcept {
#ifdef PROTOZERO_USE_BUILTIN_BSWAP
*reinterpret_cast<uint32_t*>(result) = __builtin_bswap32(*reinterpret_cast<const uint32_t*>(data));
return __builtin_bswap32(value);
#else
result[3] = data[0];
result[2] = data[1];
result[1] = data[2];
result[0] = data[3];
return ((value & 0xff000000) >> 24) |
((value & 0x00ff0000) >> 8) |
((value & 0x0000ff00) << 8) |
((value & 0x000000ff) << 24);
#endif
}
/**
* Swap 8 byte value (int64_t, uint64_t, double) between endianness formats.
*/
template <>
inline void byteswap<8>(const char* data, char* result) {
inline uint64_t byteswap_impl(uint64_t value) noexcept {
#ifdef PROTOZERO_USE_BUILTIN_BSWAP
*reinterpret_cast<uint64_t*>(result) = __builtin_bswap64(*reinterpret_cast<const uint64_t*>(data));
return __builtin_bswap64(value);
#else
result[7] = data[0];
result[6] = data[1];
result[5] = data[2];
result[4] = data[3];
result[3] = data[4];
result[2] = data[5];
result[1] = data[6];
result[0] = data[7];
return ((value & 0xff00000000000000ULL) >> 56) |
((value & 0x00ff000000000000ULL) >> 40) |
((value & 0x0000ff0000000000ULL) >> 24) |
((value & 0x000000ff00000000ULL) >> 8) |
((value & 0x00000000ff000000ULL) << 8) |
((value & 0x0000000000ff0000ULL) << 24) |
((value & 0x000000000000ff00ULL) << 40) |
((value & 0x00000000000000ffULL) << 56);
#endif
}
inline void byteswap_inplace(uint32_t* ptr) noexcept {
*ptr = byteswap_impl(*ptr);
}
inline void byteswap_inplace(uint64_t* ptr) noexcept {
*ptr = byteswap_impl(*ptr);
}
inline void byteswap_inplace(int32_t* ptr) noexcept {
auto bptr = reinterpret_cast<uint32_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(int64_t* ptr) noexcept {
auto bptr = reinterpret_cast<uint64_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(float* ptr) noexcept {
auto bptr = reinterpret_cast<uint32_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(double* ptr) noexcept {
auto bptr = reinterpret_cast<uint64_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
} // end namespace detail
} // end namespace protozero
#endif // PROTOZERO_BYTESWAP_HPP